294 A BOOK OF -WHALES 



The genus PLATANISTA may be thus distinguished 

 from its allies : -There is no dorsal fin ; the pectorals 

 are large and truncated at the extremity ; teeth not 

 so numerous as in Inia, some twenty-nine in each 

 half of each jaw. Scapula with the acromion 

 coinciding with the anterior margin of the bone, and 

 a rudimentary coracoicl process only. In the skull 

 there are enormous maxillary crests. 



The most remarkable feature of the cervical region 

 of the spinal column is the independence and the 

 comparatively great thickness of the individual 

 vertebrae. There is a fairly strongly-marked odon- 

 toid process on the axis, a very rare feature in 

 whales. The thoracic vertebrae are locked together 

 in a way which is also peculiar to Platanista among 

 whales ; but the mode of attachment of the ribs is 

 on the whole like that of Inia. The first seven of 

 these are attached to the transverse process of their 

 own vertebrae and to the centra of the vertebra in 

 front. 



There are eight lumbar vertebrae. The sternal 

 ribs, as in Inia, are cartilaginous. The sternum is 

 not so modified as is that of Inia. It consists of 

 three pieces placed end to end, of which the middle 

 one, at any rate, shows traces of its double origin by 

 a suture running down it longitudinally. To the 

 sternum four ribs are attached. The main peculiarity 

 of the scapula (quite unique among whales) has been 

 pointed out in the definition of the genus. As in 

 Inia, the humerus is unusually long. The most 



